ICSharpCode.AvalonEdit.Document.TextDocument.RunUpdate C# (CSharp) Method

        public IDisposable RunUpdate()
        {
            BeginUpdate();
            return new CallbackOnDispose(EndUpdate);
        }

        /// <summary>
        /// Replaces the text in a line.
        /// If only whitespace at the beginning and end of the line was changed, this method
        /// only adjusts the whitespace and doesn't replace the other text.
        /// </summary>
        public static void SmartReplaceLine(this TextDocument document, DocumentLine line, string newLineText)
        {
            if (document == null)
            {
                throw new ArgumentNullException("document");
            }
            if (line == null)
            {
                throw new ArgumentNullException("line");
            }
            if (newLineText == null)
            {
                throw new ArgumentNullException("newLineText");
            }

            string newLineTextTrim = newLineText.Trim(whitespaceChars);
            string oldLineText     = document.GetText(line);

            if (oldLineText == newLineText)
            {
                return;
            }

            int pos = oldLineText.IndexOf(newLineTextTrim, StringComparison.Ordinal);

            if (newLineTextTrim.Length > 0 && pos >= 0)
            {
                using (document.RunUpdate())
                {
                    // find whitespace at beginning
                    int startWhitespaceLength = 0;
                    while (startWhitespaceLength < newLineText.Length)
                    {
                        char c = newLineText[startWhitespaceLength];
                        if (c != ' ' && c != '\t')
                        {
                            break;
                        }
                        startWhitespaceLength++;
                    }
                    // find whitespace at end
                    int endWhitespaceLength = newLineText.Length - newLineTextTrim.Length - startWhitespaceLength;

                    // replace whitespace sections
                    int lineOffset = line.Offset;
                    document.Replace(lineOffset + pos + newLineTextTrim.Length, line.Length - pos - newLineTextTrim.Length, newLineText.Substring(newLineText.Length - endWhitespaceLength));
                    document.Replace(lineOffset, pos, newLineText.Substring(0, startWhitespaceLength));
                }
            }
            else
            {
                document.Replace(line.Offset, line.Length, newLineText);
            }
        }